(1) Field of the Invention
The present invention relates to a spark-ignition engine.
(2) Description of Related Art
Conventionally, as an engine, there is an engine in which a throttle body is mounted to a front portion of a collector portion of an intake manifold and a gas mixer is mounted to the front portion of the collector portion, though a gas regulator is not mounted to the engine.
In the conventional engine, the gas regulator is not always mounted to the engine and it is impossible to integrate the gas supply device with the engine.